英文:
golang struct from other package
问题
你在做的时候出错了。错误信息显示在结构字面量中的字段s是未知的。这是因为在Built_in结构体中，字段s的访问权限是私有的，无法从外部包访问。
要解决这个问题，你可以将s字段的访问权限更改为公共的。在base_structs.go文件中，将s字段的声明改为大写字母开头，这样它就可以从外部包访问了。修改后的代码如下：
package structs
type Built_in_func func([]string)
type Built_in struct {
S string
F Built_in_func
}
然后，在main.go文件中更新你的代码，使用大写字母开头的s字段：
var builtin_list []structs.Built_in
builtin_list = append(builtin_list, structs.Built_in{S: "exit", F: builtin.Exit})
builtin_list = append(builtin_list, structs.Built_in{S: "hi", F: builtin.Hi})
这样就可以解决你遇到的错误了。
英文:
Situation:
I've the following project structure:
root
parser
parser.go
builtin
exit.go
hi.go
structs
base_structs.go
main.go
.. and the base_structs.go file looks like this:
package structs
type Built_in_func func([] string)
type Built_in struct {
s string
f Built_in_func
}
I've imported the package in my main.go and I'm referencing the struct with structs.Built_in.
This is what I'm trying to do:
var builtin_list [] structs.Built_in
builtin_list = append(builtin_list, structs.Built_in{s:"exit", f:builtin.Exit})
builtin_list = append(builtin_list, structs.Built_in{s:"hi", f:builtin.Hi})
But I'm getting this error:
> unknown structs.Built_in field 's' in struct literal
Question:
What am I doing wrong?
答案1
得分: 14
在Go语言中，一个名称在包外的可见性取决于它的首字母是否大写。
所以，字段s实际上在包structs外部是不可见的，你会得到那个错误。
如果你像这样定义你的结构体（注意大写）：
type Built_in struct {
S string
F Built_in_func
}
那么这将起作用（同样是大写）：
structs.Built_in{S:"exit", F:builtin.Exit}
你可以在这里阅读更多信息：
https://golang.org/doc/effective_go.html#names
英文:
In Go, the visibility of a name outside a package is determined by whether its first character is upper case.
So the field s is actually not visible from outside the package structs and you get that error.
If you define your struct like (note the upper case):
type Built_in struct {
S string
F Built_in_func
}
Then this will work (again the upper case):
structs.Built_in{S:"exit", F:builtin.Exit}
You can read more here:
通过集体智慧和协作来改善编程学习和解决问题的方式。致力于成为全球开发者共同参与的知识库，让每个人都能够通过互相帮助和分享经验来进步。
评论